Composite tile product

ABSTRACT

A self-adhering composite tile product is configured to be bonded to a wall or floor subsurface. The composite tile product includes a first membrane including a modified bitumen material and a second membrane including a modified bitumen material. The composite tile product further includes a reinforcing mat, including a plurality of fibers, that is captured between the first and second membrane, and an adhesive layer on an exposed surface of one of the first and second membranes and configured to bond to said subsurface.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.61/582,902, filed Jan. 4, 2012, the entire disclosure of which is herebyincorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates generally to composite articles, and moreparticularly, to a self-adhering composite tile product.

BACKGROUND OF THE INVENTION

Laying of rigid tiles typically involves spreading or trowelling asuitable adhesive on a substrate, setting the tiles into the adhesiveand permitting the adhesive to cure for about 12-24 hours. Thereafter,any joints between the tiles are grouted and the grout must cure forapproximately 24 more hours before the tile surface is trafficable. Evenfor comparatively small tiling jobs, therefore, the process generallyrequires about 36 or more hours of adhesive and grout curing time inaddition to the time devoted to adhesive, tile and grout placement.

In addition, cracking of tile and similar finish layers is a commonproblem in the flooring and general construction industries,necessitating costly repair as well as causing safety hazards andpotential contractor liability. When tile or other finish flooring islaid over and bonded to construction board or a subfloor having cracksor joints, there exists a tendency for the tile or finish flooring tocrack in these areas, due, inter alia, to shifting of the subsurface,shrinkage, thermal movement, settling, etc. This is true whether thetile is ceramic, natural stone, wood or other rigid or substantiallyrigid tile or finish flooring.

Further, truly rigid veneer finish layers such as ceramic tile and thelike, because of their inherent brittleness, are subject to failure evenunder normal pedestrian or light-duty vehicular traffic, notwithstandingthe degree of cracking in the subsurface over which the finish layersmay be laid. Thus, great importance is attached to the physicalcharacteristics of the materials situated between the tiles and thesubsurface. If such materials are too hard, then they will noteffectively accommodate subsurface crack or joint expansion andcontraction; if too soft (and especially also if relatively thick), theintervening materials may differentially compress whereby the rigidveneer may fracture under normal shear loading.

BRIEF SUMMARY OF THE INVENTION

The following presents a simplified summary of the invention in order toprovide a basic understanding of some example aspects of the invention.This summary is not an extensive overview of the invention. Moreover,this summary is not intended to identify critical elements of theinvention nor delineate the scope of the invention. The sole purpose ofthe summary is to present some concepts of the invention in simplifiedform as a prelude to the more detailed description that is presentedlater.

In accordance with one aspect, a self-adhering composite tile product isconfigured to be bonded to a wall or floor subsurface, comprising afirst membrane comprising a modified bitumen material and a secondmembrane comprising a modified bitumen material. The composite tileproduct further comprises a reinforcing mat, comprising a plurality offibers, that is captured between the first and second membrane, and anadhesive layer on an exposed surface of one of the first and secondmembranes and configured to bond to said subsurface.

In accordance with another aspect, a self-adhering composite tileproduct is configured to be bonded to a wall or floor subsurface,comprising a first membrane comprising a modified bitumen material with35-70% by weight of bitumen and a second membrane comprising a modifiedbitumen material with 35-70% by weight of bitumen, the second membranehaving dimensions substantially coextensive with the first membrane. Thecomposite tile product further comprises a reinforcing mat, comprising aplurality of fibers, that is captured between the first and secondmembrane. The composite tile product further comprises a first adhesivelayer on an exposed surface of one of the first and second membranes andconfigured to bond to said subsurface, and a second adhesive layer on anexposed surface of the other of the first and second membranes.

It is to be understood that both the foregoing general description andthe following detailed description present example and explanatoryembodiments of the invention, and are intended to provide an overview orframework for understanding the nature and character of the invention asit is claimed. The accompanying drawings are included to provide afurther understanding of the invention and are incorporated into andconstitute a part of this specification. The drawings illustrate variousexample embodiments of the invention, and together with the description,serve to explain the principles and operations of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other aspects of the present invention will becomeapparent to those skilled in the art to which the present inventionrelates upon reading the following description with reference to theaccompanying drawings, in which:

FIG. 1 is an exploded view of an example composite tile product;

FIG. 2 is a top plan view of an example method of application of thecomposite tile product;

FIG. 3 is a top plan view of another example method of application ofthe composite tile product; and

FIG. 4 is similar to FIG. 3, but illustrates yet another example methodof application that may be readily adapted at an installation site toaccommodate site-specific installation requirements.

DESCRIPTION OF EXAMPLE EMBODIMENTS

Example embodiments that incorporate one or more aspects of the presentinvention are described and illustrated in the drawings. Theseillustrated examples are not intended to be a limitation on the presentinvention. For example, one or more aspects of the present invention canbe utilized in other embodiments and even other types of devices.Moreover, certain terminology is used herein for convenience only and isnot to be taken as a limitation on the present invention. Still further,in the drawings, the same reference numerals are employed fordesignating the same elements.

Conventional and current self-adhering tile assemblies are successfulfor wall applications only due to their lack of compressive loadstrength in the makeup of the assembly. When used on floors, theseproducts fail due to cracking under impact loads, expansion/contractionof the substrate and shrinkage cracking of the concrete substrate. Thecurrent ASTM C-627 standards address these issues. Moreover,conventional wisdom has held that the use of bitumen (e.g., rubberizedasphalt) may stain or leach colors (especially black) into attachedfinished surfaces, may have a displeasing odor, and/or may have pooradhesive strength.

The composite tile system 10 described herein is a self-adhering,reinforced tile mounting system that addresses the above historicalproblems and also reduces, such as eliminates, the need for messyadhesives and mortars, reducing dusty and caustic conditions in the homeand commercial environment. The composite tile system 10 is intended asan “all-in-one” installation product. The composite tile system 10described herein can incorporate various materials to greatly improveperformance, such as fiberglass or polyester reinforcement, bariumsulfate filler and/or other compounds such as asphalt and calciumcarbonate to give the composite tile system the compressive loadstrength to withstand these impact loads also acting as a crackisolation membrane and sound reduction assembly.

The composite tile system 10 meets or exceeds various specifications forceramic tile and dimensional stone, such as the specifications ANSIA-118.12-2008 revised (i.e., crack isolation membranes for thin-setceramic tile and dimensional stone installation), and ASTM C-627 (i.e.,used to predict a floor's performance under several different loads,commonly referred to as the “Robinson Test”), both of which are herebyincorporated herein by reference. Currently, this the only compositetile system product produced that meet these standards.

Turning to the shown example of FIG. 1, the composite tile product 10described herein is designed to provide a self-adhering adhesive systemconfigured to be bonded to a wall, countertop, or floor subsurface 14,such as for hard surface flooring and wall products most commonly usedon decorative finish layer 12. The composite tile product 10 isdesirably constructed as an individual self-adhering tile unit, and asshown in the attached drawings, is an intermediate product locatedbetween the decorative finish layer 12 and an underlying substrate orsubsurface 14. For example, the composite tile product 10 can be usedwith ceramic tile, hardwood flooring, etc. but can also be applied toconstruction board or other materials, such as drywall, concrete, mudbeds, plywood, hardwood, backer board, existing ceramic and porcelaintile, VCT/VAT, metal, painted floors, and many others.

The decorative finish layer 12 may be suitably be formed of any rigid tosubstantially rigid finishing material, e.g., ceramic tile, quarry tile,glass, natural or synthetic stone, marble, slate, hardwood, parquet,cement terrazzo tiles, epoxy terrazzo, vinyl tile, V.A. tile and thelike. For example, the decorative surface may be a single, rigid,typically ceramic floor or wall tile having a thickness of approximately3/16 inch to about ½ inch, although generally rigid tiles or similarfinish layers of greater or lesser thickness may be suitably employed.Further, although illustrated as being of generally squareconfiguration, the finish layer 12, which establishes the perimetricalconfiguration of the entire composite tile product 10, may also betriangular, rectangular, pentagonal, hexagonal, or other regular orirregular polygonal and/or curvilinear shape. The composite tile product10 can be applied at the factory, distributor or sold as a stand-aloneproduct at a DIY or retail store.

In one example, as shown in FIG. 1, the composite tile system 10 caninclude five layers, although more or less layers are contemplated. Forexample, first and second membranes 20, 22 can be provided that aremodified adhesive components. Both of the first and second membranes 20,22 can comprise a modified bitumen material that may be the same ordifferent for each of the first and second membranes 20, 22. Themodified bitumen material can include some or all of modified bitumen(e.g., asphalt), SBS polymers, process oils, hydrocarbon resins, and/oran antioxidant mixed with high density fillers designed to abate impactand airborne sound transmission.

In one example, the modified bitumen material of the first and secondmembranes 20, 22 comprises 35-70% by weight of bitumen, such as 40-60%by weight. In addition or alternatively, the modified bitumen materialcomprises 1-10% by weight of process oils, such as 3-8% by weight. Inaddition or alternatively, the modified bitumen material comprises 1-10%by weight of hydrocarbon resin, such as 3-8% by weight. In addition oralternatively, the modified bitumen material comprises 1-10% by weightof antioxidants, such as 3-8% by weight. In addition or alternatively,the modified bitumen material comprises 20-60% by weight of at least onehigh-density filler material. In addition or alternatively, the modifiedbitumen material comprises 5-15% by weight of calcium carbonate.

Unlike typical modified bitumen membranes that leech asphalt residue toan attached substrate, the composite tile system with specialty fillersdescribed above and/or including barium sulfate, inhibit the leeching ofthe asphalt compound into the substrate to which it's bonded up to 150degrees F. For example, normal asphalt based membranes will leechasphalt residue in relatively light-bodied stone used for flooring suchas limestone, travertine and other absorptive tile products. Aromaticoils, which are typical in roofing membranes, have been reduced to thepoint of having no “tobacco juice” effect on soft marbles and lightcolored grout. Additionally, the black color of the product hasvirtually no effect on light, soft bodied tiles. Calcium carbonate andstyrene-butadiene-styrene block copolymer, such as 10-20% by weight ofthe modified bitumen material, can be used together with or asalternative products to the above. Other bonding systems do not addressthe issues of compressive load failure, adhesive leaching into thesurrounding areas and adjustability of the composite tile system. Otherchemicals, such as ground mica, can be used for thermal insulation andmechanical properties which allows it to be cut, punched or stamped tosize. Barium sulfate can also be used to contribute to sound reductioncapabilities and reduce both STC (airborne sound) and IIC (impact sound)sound transmission between floors and walls.

Additionally, either or both of the first and second membranes 20, 22can have a geometry that is complementary, such as substantially similarto, the geometry of the finish layer 12. Preferably, the first andsecond membranes 20, 22 have substantially similar geometries such thatouter perimeters of thereof are substantially coextensive when the firstand second membranes 20, 22 are arranged in a covering relationship(e.g., see FIG. 1).

Additionally, the composite tile product 10 is preferably able towithstand a minimum of 4000 psi loading when combined with finish layer12. The American National Standard (ANSI) specifications (e.g., see ANSIA-118.12-2008 revised) for the installation of ceramic tile prescribe aminimum requirement of 50 psi shear bond strength between the tile andthe substrate to which it is attached. As such, the composite tileproduct 10 can further include a reinforcing mat 24 comprising aplurality of fibers. In one example, the reinforcing mat 24 can becaptured between the first and second membranes 20, 22, and may beprovided as a generally central layer. The reinforcing mat 24 may have asimilar geometry to the first and second membranes 20, 22, and may besubstantially coextensive therewith. The reinforcing mat 24 can befixedly attached to either or both of the first and second membranes 20,22, or could instead be provided as a free-floating layer between thefirst and second membranes 20, 22. It is understood that use of the term“mat” is not intended to provide a limitation. For example, thereinforcing mat 24 may be unitary or may be formed of a plurality ofelements, and/or may be continuous or dis-continuous. In one example,the reinforcing mat 24 comprises a non-woven fabric sheet. In additionor alternatively, the reinforcing mat 24 comprises at least one ofpolyester, polypropylene, nylon, and/or glass fiber, and/or combinationsthereof. Preferably, a nonabsorptive material, such as a polyester fibersheet, may be used. A nonabsorptive sheet is preferable because a sheetwhich absorbs water tends to swell, forming pockets under the floor orother finish layer, increasing the likelihood of compression cracking.Other materials are suited for reinforcement as well. Thus, the use ofthe reinforcing mat 24 can provide strength to the composite tileproduct 10, and preferably contributes to the 4000 psi static loadingfor impact force and also the shear bond strength in excess of 50 psibetween the finish layer 12 (e.g., tile, etc.) and the subsurface 14 towhich it is attached.

To facilitate installation of the finish layer 12 on-site, the compositetile product 10 can further include a first adhesive layer 30 on anexposed surface of one of the first and second membranes 20, 22.Similarly, a second adhesive layer 32 can be provided on an exposedsurface of the other of the first and second membranes 20, 22. Byexposed surface, it is referred to the outer surface of each of thefirst and second membranes 20, 22 that is bonded to the finish layer 12and/or subsurface 14. At least one of the first and second adhesivelayers 30, 32, and preferably both adhesive layers 30, 32, areconfigured to bond to the subsurface 14 such that he composite tileproduct 10 does not have to be oriented in a specific manner duringinstallation. Similarly, at least one of the first and second adhesivelayers 30, 32, and preferably both adhesive layers 30, 32, areconfigured to bond to the finish layer 12. Thus, the composite tileproduct 10 can be self-bonding to the finish layer 12 and/or subsurface14. Additionally, the first and second adhesive layers 30, 32 caninclude a pressure sensitive adhesive to permit easy placement of thecomposite tile product 10 onto the subsurface 14.

One or more release sheets 34 can be provided for covering the first andsecond adhesive layers 30, 32 and are configured to prevent inadvertentadherence of the first and second adhesive layers 30, 32 prior toinstallation (e.g., during shipping and storage). For example, therelease sheets 34 can include release film or paper to be removed anddiscarded during the application of the composite tile product 10. Therelease sheets 34 can be independent such that the removal of one doesnot affect the other. Thus, when it is desired to install the compositetile product 10, the release sheets 34 are removed and the compositetile product 10 is pressed onto the subsurface 14.

In addition or alternatively, the exposed surfaces of the first andsecond membranes 30, 32 and/or the finish layer 12 and/or subsurface 14may be coated in situ with an appropriate curable adhesive, such asmortar or similar compound prior to placement of the composite tileproduct 10 to affect the desired bond therebetween. For example, aprimer material 40 can be applied to either or both of the first andsecond membranes 20, 22 and is configured to bond directly to thesubsurface 14. Preferably, the primer material 40 can also be configuredto bond directly to the finish layer 12 such that the same primermaterial 40 can be used for both. The primer material 40 can include asynthetic rubber dispersion in water with a proprietary mixture fordelayed set of the composite system. For example, the primer material 40can comprise a vinyl acetate copolymer emulsion. The primer material 40can be applied by a roller or trowel. The primer material 40 functionsas an aid for adhesion of the composite tile product 10 to thesubsurface 14 (and/or finish layer 12), and may also delay the initialproduct set to provide the installer “open time” to adjust, reposition,and align tiles before final set time. Moreover, the primer material 40can reduce, such as eliminate, wait time between setting the finishlayer 12 (e.g., tiles, etc.) and grouting, if grout is used. Preferably,the primer material 40 is configured to provide “open time” on a drywallsubsurface 14 in the range of about 30 seconds to about 60 seconds,and/or “open time” on a concrete subsurface 14 in the range of about 3minutes to about 5 minutes, or possibly even hours. Irrespective of howthe composite tile product 10 is bonded to the finish layer 12 orsubsurface 14, the spaces between adjacent finish layers 12 can befilled with grout or other conventional joint filler material uponsufficient bonding of the composite tile product 10 to the subsurface14.

As shown in FIG. 2, one of many presently contemplated beneficialapplications or uses for the composite tile products 10 is illustrated.More particularly, an existing floor or wall subsurface 14 that may ormay not have cracks and/or joints (one of which is own at 28) is firstprepared for application of the composite tile product 10. The compositetile product 10 may be used over any type of existing floor or wall,such as concrete, concrete block, masonry, concrete backer board,plywood, particle board, gypsum wallboard, steel, etc. Preferably,installations begin with a clean, dry substrate free of wax, sealers,dirt, grease, oil or other bond-breakers.

The size and/or shape of the composite tile product 10 should beselected so as to be sufficient to not only cover the subsurface 14, butalso accommodate expansion and contraction of the joints or cracks 28whereby reflective cracking in the finish layer 12 may be effectivelyavoided. In one example, composite tile products 10 may be relativelysquare with a 12 inch by 12 inch dimension, and may be laid side-by-sideto cover meandering cracks 28 such that several inches of the finishlayer 12 extends beyond the ends and to either side of the crack 28. Forshorter, narrower, and/or less erratic cracks, composite tile products10 of smaller size (e.g.,. 6 inch by six inch or other size) may be usedto effect the desired subsurface crack or expansion joint coverage.Further, only those composite tile products 10 that are used to coverthe crack 28 are shown in FIG. 2 (e.g., four finish layers 12 areinstalled, with a fifth prepared to be installed over an in-placecomposite tile product 10), and it is understood that additionalcomposite tile products 10 and associated finish layers 12 will be laidabout as is necessary to cover the balance of the subsurface 14 intendedto be covered. It will be further appreciated that the composite tileproducts 10 maybe applied over new or otherwise unmarred subsurfaces 14.And, regardless of the condition of the subsurface 14, the compositetile products 10 may be laid in side-by-side abutting relation or withpredetermined spacing therebetween to establish joints to be filled byany appropriate grout or similar joint-filling compound.

During installation, the installer can begin tiling the finish layers 12on the subsurface 14 by peeling off the protective release sheet 30, 32and attaching the composite tile product 10 thereto. Next, the finishlayer 12 with attached composite tile product 10 is carefully positionedit into place on the subsurface 14. Alternatively, the composite tileproduct 10 can be positioned into place on the subsurface 14, and thenthe finish layer 12 can be positioned it into place on top of thein-place composite tile product 10. If desired, the finish layer 12 canbe repositioned while the primer material 40 is still wet and beforesignificant pressure has been applied. Repositioning of tile is bestachieved while primer material 40 is still in liquid state. As shown inFIG. 1, the primer material 40 can be applied between the finish layer12 and the composite tile product 10, and may also be applied betweenthe composite tile product 10 and the subsurface 14. Once the finishlayer 12 is set as desired, significant pressure can be applieduniformly across the face of the finish layer 12 to securely bond it tothe subsurface 14. Generally, the first and second membranes 20, 22 arepressure sensitive. Once pressure is applied, a more permanent bond willtake place and a full bond will take, for example, 12-24 hours. Groutcan be applied between adjacent finish layers 12 (e.g., in spacesbetween adjacent tiles, etc.), if desired.

FIGS. 3-4 illustrate another example method of application of compositetile product construction that may be readily adapted at an installationsite to accommodate site-specific installation requirements. Forexample, as shown, the finish layer 12′ can be constructed as amulti-tile unit including a plurality of generally rigid tiles. In theillustrated example, nine tiles are arranged in three rows with threetiles in each row, although tile arrangements of greater or lessernumber are contemplated. The finish layer 12′ may be formed of any ofthe rigid to substantially rigid materials identified herein, and mayhave any geometry. The multi-tile unit of the finish layer 12′ can bedisposed, such as fused, adhesively bonded, or otherwise fixedlyattached on a layer of support material 50. The support material 50 caninclude a relatively thin, flexible mesh of natural or syntheticmaterial such as polyester, glass fiber, polypropylene, nylon, or thelike. The tiles are fixed to the support material 50 to form gaps orjoints 52 configured to receive grout or the like once the finish layer12′ is adhered to the composite tile product 10 and subsurface 14. Asshown in FIG. 4, the subsurface 14 or adjoining structures 60 maypresent space constraints or other physical constraints that wouldotherwise complicate or prevent placement of an entire finish layer 12′and/or composite tile product 10. Should the installer encounter asituation where it is desirable or necessary to modify the tilearrangement, the installer can easily cut the support material 50 withinthe area of the joints 52 using an appropriate knife, shears, scissors,or the like to the desired shape or pattern. Similarly, the underlyingcomposite tile product 10 can likewise be cut to match the desiredmodified shape of the finish layer 12′. Although different examples areshown in FIGS. 3-4, it is understood that various geometries or patternscan be used.

The overall thickness of the composite tile product 10 can range fromabout 5 mils to about 150 mils (about 0.005 inches to about 0.150inches), though other sizes are contemplated. It is further contemplatedthat the first and second membranes 20, 22 can have substantiallysimilar, or even different, thicknesses.

Once the composite tile system 10 is installed, it can also function asa crack isolation membrane to inhibit, such as prevent, cracking of thedecorative surface. It can also function as a moisture vapor barrier toreduce substrate water migration and radon, provide positive andnegative waterproof protection of the assembly and/or sound insulation.

The composite tile system 10 may include additional features asdescribed in two separate documents both entitled “composite tilesystem,” which are both hereby incorporated herein by reference. Thesedocument relate to U.S. patent application Ser. Nos. 07/960,130 and08/629,836, which include priority claims dating to at least Oct. 26,1987.

The invention has been described with reference to the exampleembodiments described above. Modifications and alterations will occur toothers upon a reading and understanding of this specification. Examplesembodiments incorporating one or more aspects of the invention areintended to include all such modifications and alterations insofar asthey come within the scope of the appended claims.

What is claimed is:
 1. A self-adhering composite tile product configuredto be bonded to a wall or floor subsurface, comprising: a first membranecomprising a modified bitumen material; a second membrane comprising amodified bitumen material; a reinforcing mat, comprising a plurality offibers, that is captured between the first and second membranes; and anadhesive layer on an exposed surface of one of the first and secondmembranes and configured to bond to said subsurface.
 2. Theself-adhering composite tile product of claim 1, further comprising asecond adhesive layer on an exposed surface of the other of the firstand second membranes.
 3. The self-adhering composite tile product ofclaim 1, wherein the reinforcing mat is fixedly attached to each of thefirst and second membranes.
 4. The self-adhering composite tile productof claim 1, wherein the reinforcing mat comprises a non-woven fabricsheet.
 5. The self-adhering composite tile product of claim 4, whereinthe reinforcing mat comprises at least one of polyester, polypropylene,and glass fiber.
 6. The self-adhering composite tile product of claim 1,further comprising a release sheet covering said adhesive layer andconfigured to prevent inadvertent adherence of said adhesive layer. 7.The self-adhering composite tile product of claim 1, wherein themodified bitumen material of the first and second membranes comprises35-70% by weight of bitumen.
 8. The self-adhering composite tile productof claim 7, wherein the modified bitumen material of the first andsecond membranes further comprises 1-10% by weight of process oils. 9.The self-adhering composite tile product of claim 7, wherein themodified bitumen material of the first and second membranes furthercomprises 1-10% by weight of hydrocarbon resin.
 10. The self-adheringcomposite tile product of claim 7, wherein the modified bitumen materialof the first and second membranes further comprises 1-10% by weight ofantioxidants.
 11. The self-adhering composite tile product of claim 7,wherein the modified bitumen material of the first and second membranesfurther comprises 20-60% by weight of at least one high-density fillermaterial.
 12. The self-adhering composite tile product of claim 7,wherein the modified bitumen material of the first and second membranesfurther comprises 5-15% by weight of calcium carbonate.
 13. Theself-adhering composite tile product of claim 1, wherein the modifiedbitumen material of the first and second membranes comprises: 35-70% byweight of bitumen; 1-10% by weight of process oils; 1-10% by weight ofhydrocarbon resin; 1-10% by weight of antioxidants; 20-60% by weight ofat least one high-density filler material; and 5-15% by weight ofcalcium carbonate.
 14. The self-adhering composite tile product of claim1, wherein the modified bitumen material of the first and secondmembranes comprises barium sulfate.
 15. The self-adhering composite tileproduct of claim 1, further comprising a primer material applied to theadhesive layer and configured to bond directly to said subsurface. 16.The self-adhering composite tile product of claim 15, wherein the primermaterial comprises a vinyl acetate copolymer emulsion.
 17. Aself-adhering composite tile product configured to be bonded to a wallor floor subsurface, comprising: a first membrane comprising a modifiedbitumen material with 35-70% by weight of bitumen; a second membranecomprising a modified bitumen material with 35-70% by weight of bitumen,the second membrane having dimensions substantially coextensive with thefirst membrane; a reinforcing mat, comprising a plurality of fibers,that is captured between the first and second membranes; a firstadhesive layer on an exposed surface of one of the first and secondmembranes and configured to bond to said subsurface; and a secondadhesive layer on an exposed surface of the other of the first andsecond membranes.
 18. The self-adhering composite tile product of claim17, wherein the modified bitumen material of the first and secondmembranes further comprises: 1-10% by weight of process oils; 1-10% byweight of hydrocarbon resin; 1-10% by weight of antioxidants; 20-60% byweight of at least one high-density filler material; and 5-15% by weightof calcium carbonate.
 19. The self-adhering composite tile product ofclaim 17, further comprising a primer material applied to the firstadhesive layer and configured to bond directly to said subsurface,wherein the primer material comprises a vinyl acetate copolymeremulsion.
 20. The self-adhering composite tile product of claim 17,wherein the reinforcing mat comprises at least one of polyester,polypropylene, and glass fiber.